Display device having an array of spatial light modulators with integrated color filters

Abstract

By selectively placing color filters with different transmittance spectrums on an array of modulator elements each having the same reflectance spectrum, a resultant reflectance spectrum for each modulator element and it's respective color filter is created. In one embodiment, the modulator elements in an array are manufactured by the same process so that each modulator element has a reflectance spectrum that includes multiple reflectivity lines. Color filters corresponding to multiple colors, such as red, green, and blue, for example, may be selectively associated with these modulator elements in order to filter out a desired wavelength range for each modulator element and provide a multiple color array. Because the modulator elements are manufactured by the same process, each of the modulator elements is substantially the same and common voltage levels may be used to activate and deactivate selected modulation.

1. A display comprising:
 a spatial light modulator having a dark state and a light state, wherein the dark state has an emission spectrum that includes substantially more visible light near one or both ends of the visible spectrum than at any wavelength of visible light not near the ends of the visible spectrum such that the dark state produces a non-black color; and 
 a filter structure disposed so as to receive light output by the spatial light modulator, wherein the filter structure is configured to attenuate substantially more visible light near at least one of the one or both ends of the visible spectrum than at one or more wavelengths of visible light not near the ends of the visible spectrum so as to darken the dark state of the spatial light modulator. 
 
     
     
       2. The display of  claim 1 , wherein the emission spectrum of the dark state includes more visible light near the blue end of the visible spectrum than at any wavelength of visible light not near the ends of the visible spectrum. 
     
     
       3. The display of  claim 2 , wherein the emission spectrum of the dark state includes a tail of second-order blue light. 
     
     
       4. The display of  claim 3 , wherein the filter structure has a transmittance spectrum that substantially attenuates the tail of the second-order blue light. 
     
     
       5. The display of  claim 2 , wherein the filter structure is configured to substantially transmit visible light between at least about 420 nanometers to about 650 nanometers in wavelength and to substantially attenuate visible light below about 420 nanometers in wavelength. 
     
     
       6. The display of  claim 1 , wherein the emission spectrum of the dark state includes substantially more visible light near the red end of the visible spectrum than at any wavelength of visible light not near the ends of the visible spectrum. 
     
     
       7. The display of  claim 6 , wherein the emission spectrum of the dark state includes a tail of first-order red light. 
     
     
       8. The display of  claim 7 , wherein the filter structure has a transmittance spectrum that substantially attenuates the tail of the first-order red light. 
     
     
       9. The display of  claim 6 , wherein the filter structure is configured to substantially transmit visible light between at least about 420 nanometers to about 650 nanometers in wavelength and to substantially attenuate visible light above about 650 nanometers in wavelength. 
     
     
       10. The display of  claim 1 , wherein the emission spectrum of the dark state includes a tail of first-order red light and a tail of second-order blue light such that the dark state produces a deep purple color. 
     
     
       11. The display of  claim 10 , wherein the filter structure has a transmittance spectrum that substantially attenuates the tail of the first-order red light and the tail of the second-order blue light. 
     
     
       12. The display of  claim 1 , wherein the spatial light modulator includes an interferometric light modulator. 
     
     
       13. The display of  claim 12 , wherein the interferometric light modulator includes:
 a reflective surface; 
 a partially reflective surface, wherein at least one of the reflective surface and the partially reflective surface is movable with respect to the other; and 
 a gap formed between the reflective surface and the partially reflective surface. 
 
     
     
       14. The display of  claim 13 , further comprising a dielectric layer disposed between the reflective surface and the partially reflective surface, wherein the thickness of the dielectric layer is sufficiently large to produce the emission spectrum of the dark state that includes substantially more visible light near the one or both ends of the visible spectrum than at any wavelength of visible light not near the ends of the visible spectrum. 
     
     
       15. The display of  claim 14 , wherein the thickness of the dielectric layer is between about 2200 Angstroms to about 2500 Angstroms. 
     
     
       16. The display of  claim 13 , wherein the partially reflective surface is fixed and the reflective surface is moveable. 
     
     
       17. The display of  claim 1 , further comprising:
 a plurality of spatial light modulators, each of the plurality of spatial light modulators having a light state and a dark state, wherein the dark state of each of the plurality of spatial light modulators has an emission spectrum that includes substantially more light near one or both ends of the visible spectrum than at any wavelength of visible light not near the ends of the visible spectrum such that the dark state of each of the plurality of spatial light modulators produces a color that resembles black; and 
 a plurality of filter structures disposed so that each of the plurality of filter structures receives light output by one of the plurality of spatial light modulators, wherein the plurality of filter structures are configured to attenuate substantially more visible light near at least one of the one or both ends of the visible spectrum than at one or more wavelengths of visible light not near the ends of the visible spectrum so as to darken the dark states of the plurality of spatial light modulators. 
 
     
     
       18. The display of  claim 17 , wherein a first group of the filter structures corresponds to substantial transmittance of red light and is associated with a first group of the spatial light modulators, a second group of the filter structures corresponds to substantial transmittance of green light and is associated with a second group of the spatial light modulators, and a third group of the filter structures corresponds to substantial transmittance of blue light and is associated with a third group of the spatial light modulators. 
     
     
       19. The display of  claim 1 , further comprising:
 a processor that is in electrical communication with said spatial light modulator, said processor being configured to process image data; and 
 a memory device in electrical communication with said processor. 
 
     
     
       20. The display of  claim 19 , further comprising:
 a first controller configured to send at least one signal to said spatial light modulator; and 
 a second controller configured to send at least a portion of said image data to said first controller. 
 
     
     
       21. The display of  claim 19 , further comprising an image source module configured to send said image data to said processor. 
     
     
       22. The display of  claim 21 , wherein said image source module includes at least one of a receiver, transceiver, and transmitter. 
     
     
       23. The display of  claim 19 , further comprising an input device configured to receive input data and to communicate said input data to said processor. 
     
     
       24. The display of  claim 1 , wherein the filter structure is configured to attenuate light via reflection. 
     
     
       25. The display of  claim 1 , wherein the filter structure is configured to attenuate light via absorption. 
     
     
       26. The display of  claim 1 , wherein the display includes a reflective display and the emission spectrum includes a reflectance spectrum. 
     
     
       27. A method of forming an image, the method comprising:
 providing a plurality of spatial light modulators, wherein each of the plurality of spatial light modulators has a light state and a dark state; 
 setting a first group of the spatial light modulators to the light state; 
 setting a second group of the spatial light modulators to the dark state; 
 outputting light from the plurality of spatial light modulators, wherein the light outputted by the second group of spatial light modulators set to the dark state includes substantially more light near one or both ends of the visible spectrum than at any wavelength of visible light not near the ends of the visible spectrum such that the dark states of the second group of spatial light modulators produces a non-black color; and 
 attenuating substantially more visible light near at least one of the one or both ends of the visible spectrum that is outputted by the spatial light modulators than at one or more wavelengths of visible light not near the ends of the visible spectrum so as to darken the dark state of the second group of spatial light modulators. 
 
     
     
       28. The method of  claim 27 , wherein the light outputted by the second group of spatial light modulators includes a tail of first-order red light and a tail of second-order blue light such that the dark state produces a deep purple color, and wherein attenuating the visible light is performed by a plurality of filter structures having a transmittance spectrum that substantially attenuates the tail of the first-order red light and the tail of the second- order blue light. 
     
     
       29. The method of  claim 27 , wherein the attenuating of visible light includes reflecting the visible light. 
     
     
       30. The method of  claim 27 , wherein the attenuating of visible light includes absorbing the visible light.